Field of the Invention
The invention relates generally to surface-modified organic semiconductors and to methods of preparing surface-modified organic semiconductors. More particularly, the invention relates to surface modification of organic semiconductors using addition reactions, such as Diels-Alder reactions, and to organic semiconductors having surfaces containing addition reaction products.
Brief Description of Related Technology
Materials comprising organic semiconductors are prone to several disadvantages, including a propensity to oxidize, degradation resulting from humidity, and the prevalence of trap states at the semiconductor/dielectric interface. Surface-modification of organic semiconductor materials may affect these and other properties, including the electronic properties (e.g., carrier density, carrier mobility, conductivity, and field-effect mobility) of the organic semiconductor materials.
For example, Calhoun et al. describe functionalization of the surface of organic semiconductors with self-assembled monolayers of perfluorinated alkyl silanes (Nature Materials, 7:84-89 (2008)). Further, Ellison et al. describe self-assembled monolayers of fluorinated and non-fluorinated alkyl silanes on rubrene single crystals (Advanced Materials, 23:502-507 (2011)). In both cases, the self-assembled monolayers are prepared from trichlorosilanes. Trichlorosilanes demonstrate several disadvantages, including a poor ability to generate uniform, regular, or well-defined films on surfaces. Additionally, due to the incompatibility of trichlorosilanes with numerous functional groups, the range of functional groups that can be appended to the trichlorosilanes is severely limited, thereby limiting the extent to which various physical and electronic properties of the organic semiconductors can be altered.
The present invention provides improved methods and compositions for surface modification of organic semiconductors.